ECU FORD MUSTANG 2003 Repair Manual

Section 412 - 02 .
3. Install a short piece of heater water hose, approximately 101 mm (4 inches) long on each heater core tube.
4. Fill the heater core and heater water hoses with water and install Plug BT-7422- B and adapter
BT- 7422- A from the radiator/heater core pressure tester in the heater water hose ends. Secure
the heater water hoses, plug and adapter with hose clamps.
5. Attach the pump and gauge assembly from the radiator/heater core pressure tester to the adapter.
6. Close the bleed valve at the base of the gauge. Pump 241 kPa (35 psi) of air pressure into the heater core.
7. Observe the pressure gauge for a minimum of three minutes.
8. If the pressure drops, check the heater water hose connections to the core tubes for leaks. If the heater water hoses do not leak, remove the heater core from the vehicle and carry out the
bench test.
Heater Core— Bench Test
1. Remove the heater core from the vehicle. For additional information, refer to Section 412 - 02 .
2. Drain all of the coolant from the heater core.
3. Connect the 101 mm (4 inch) test heater water hoses with plug and adapter to the core tubes. Then connect the radiator/heater core pressure tester to the adapter.
4. Apply 241 kPa (35 psi) of air pressure to the heater core. Submerge the heater core in water.
5. If a leak is observed, install a new heater core. Klj . 38 ba
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The spring lock coupling is a refrigerant line coupling held together by a garter spring inside a circular
cage.
zWhen the coupling is connected together, the flared end of the female fitting slips behind the
garter spring inside the cage of the male fitting.
z The garter spring and cage then prevent the flared end of the female fitting from pulling out of
the cage.
z Three O- ring seals are used to seal between the two halves of the A/C condenser core
couplings. All other couplings have two O- ring seals.
z Use only the O- ring seals listed in the Ford Master Parts Catalog for the spring lock coupling.
z A plastic indicator ring is used on the spring lock couplings of the A/C evaporator core to
indicate, during vehicle assembly, that the coupling is connected. Once the coupling is
connected, the indicator ring is no longer necessary but will remain captive by the coupling near
the cage opening.
z The indicator ring may also be used during repair operations to indicate connection of the
coupling.
z An A/C tube lock coupling clip (19E746) may be used to secure the coupling but is not required.
Service Gauge Port Valves
The high- pressure service gauge port valve is located on the A/C manifold and tube.
The low pressure service gauge port valve is located on the suction accumulator. 2 — Female fitting (part of 19860)
3 19E746 A/C tube lock coupling clip
4 19E576 A/C tube lock coupling spring
5 — Cage (part of 19D690)
6 — O-
ring seals (part of 19D690) 7 — Male fitting (part of 19835)
Item Part
Number Description
1 19D702 A/C charging valve cap
2 19D701 Low pressure service gauge port valve (part of
19C836)
3 19D701 Schrader-
type valve 4 — O-
ring seal (part of 19D701) 5 19D701 High pressure service gauge port valve (part of Klj . 9 ba
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The boost pressure gauge on the instrument cluster receives and measures the boost pressure
directly from the intake manifold. The boost pressure gauge will display between 0.0-
0.48 kpa (0.0-10
psi) boost pressure dependent upon accelerator position, engine load, and engine rpm.
LOW FUEL Level Indicator
The low fuel level indicator is hardwired from the fuel sender to the instrument cluster. The instrument
cluster will illuminate the low fuel indicator when the usable fuel quantity is less than 1/8 tank (15%) of
fuel tank capacity.
Oil Pressure Gauge
The oil pressure gauge is hardwired from the oil pressure switch to the instrument cluster. The oil
pressure gauge will indicate either normal or no oil pressure.
CHECK FUEL CAP
The CHECK FUEL CAP indicator is used to indicate significant leaks in the fuel tank evaporative
system due to a loose fuel cap. Fuel tank pressure is monitored by the PCM. If a leak is detected the
PCM signals a fault to the instrument cluster via the SCP network. Once the PCM has detected a
loose fuel cap and the CHECK FUEL CAP indicator is illuminated, the indicator will remain illuminated
until the fuel cap is secured and the vehicle has been running for several minutes. For additional
information, refer to the Powertrain Control/Emissions Diagnosis (PC/ED) manual.
BRAKE Warning Indicator
The BRAKE warning indicator activates when the generic electronic module (GEM) detects the ignition
switch circuits are in the RUN state, when the GEM detects low brake fluid level, or that the parking
brake is applied. The BRAKE warning indicator will prove out starting when the GEM detects that the
ignition circuits have made a transition to RUN or START from OFF, ACC, or keyout and ending when
either three seconds have elapsed or when the GEM detects the ignition circuits have made a
transition to OFF, ACC, or keyout.
Safety Belt Warning Indicator
The safety belt switch is hardwired to the GEM. The safety belt warning indicator will be illuminated
when the GEM sends a ground signal to the instrument cluster.
ABS Warning Indicator
The ABS warning indicator will be illuminated when the anti- lock brake control module sends a ground
signal to the instrument cluster. The prove- out of the ABS indicator is controlled by the anti- lock brake
control module.
SERVICE ENGINE SOON Indicator
The SERVICE ENGINE SOON indicator receives its signal from the PCM over the SCP network. If the
instrument cluster does not receive a message from the PCM within five seconds, the instrument
cluster will illuminate the SERVICE ENGINE SOON indicator and log a diagnostic trouble code (DTC).
High Beam Indicator
The high beam indicator will illuminate when the steering column multifunction switch is in the high
beam position by sending a battery signal to the instrument cluster. Right and Left Turn Indicator Klj . 3 ba
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3. If an obvious cause for an observed or reported concern is found, correct the cause (if possible)
before proceeding to the next step.
4. If the concern remains after the inspection, connect the diagnostic tool to the data link connector (DLC) located beneath the instrument panel and select the vehicle to be tested from the
diagnostic tool menu. If the diagnostic tool does not communicate with the vehicle:
zcheck that the program card is correctly installed.
z check the connections to the vehicle.
z check the ignition switch position.
5. If the diagnostic tool still does not power up, refer to the diagnostic tool operating manual.
6. Carry out the DATA LINK DIAGNOSTICS test. If the diagnostic tool responds with: zCKT914, CKT915 OR CKT70 = ALL ECUS NO RESP/NOT EQUIP, refer to Section 418 -
00 .
z NO RESP/NOT EQUIP for the instrument cluster, Go To Pinpoint Test A or for the
generic electronic module (GEM), Go To Pinpoint Test W .
z SYSTEM PASSED, retrieve and record the continuous diagnostic trouble codes (DTCs),
erase the continuous DTCs and carry out the self- test diagnostics for the instrument
cluster or the GEM.
7. If the DTCs retrieved are related to the concern, go to the Instrument Cluster Diagnostic Trouble Code (DTC) Index or the GEM Diagnostic Trouble Code Index to continue diagnostics.
8. If no DTCs related to the concern are retrieved, proceed to the Symptom Chart to continue diagnostics.
Instrument Cluster Self- Diagnostic Mode
To enter the instrument cluster self- diagnostic mode, press and hold the instrument cluster
SELECT/RESET button, turn the ignition switch to the RUN position, and then continue pressing the
SELECT/RESET button (five seconds) until tESt is displayed in the odometer. The SELECT/RESET
button must be released within three seconds of the odometer tESt display to begin the self- diagnostic
mode. Press the SELECT/RESET button to advance through the following steps until dtc is displayed.
Depressing the SELECT/RESET button will display any stored continuous DTCs before proceeding to
the next step. z
Engine coolant level
z Accessory drive belt
z Engine oil level
z Parking brake position switch
z Brake fluid level
z Boost gauge pressure line „
5 (15A)
„ 7 (15A)
„ 11 (15A)
„ 13 (15A)
„ 21 (5A)
„ 23 (15A)
„ 24 (30A)
„ 29 (15A)
„ 30 (15A)
„ 32 (15A)
„ 34 (20A)
„ 35 (15A)
„ 37 (5A)
„ 38 (20A)
„ 39 (5A)
z Circuitry Klj . 5 ba
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To exit the instrument cluster self-
diagnostic mode, turn the ignition switch to the OFF position or press
and hold the SELECT/RESET button for three or more seconds and release. z
93- 102 = 6.9- 9.1 volts (low voltage)
z 115- 124 = 8.5- 10.7 volts (norm band start)
z 215- 225 = 15.8- 18 volts (norm band end)
z 230- 241 = 16.9- 19.1 volts (high voltage) rhEo Displays the present decimal rheostat dimming input, 0-
255 (used when requesting
assistance from the hotline). rhi
rhS rho Not used.
Cr Displays the present RUN/START sense input. Display will show -
h for high input with
the ignition switch in the START position and - L for low input with the ignition switch in
the RUN position. PA-
PE7 Not used.
GAGE Repeats test display cycle.
Instrument Cluster Diagnostic Trouble Code (DTC) Index Diagnostic
Tool
Displayed DTC Self-
Diagnostic
Mode Displayed DTC Description Source Action
B1202 9202 Fuel Sender
Open Circuit Instrument
Cluster Go To Pinpoint Test B .
B1204 9204 Fuel Sender
Short to Ground Instrument
Cluster Go To Pinpoint Test B .
B1317 9317 Battery Voltage
High Instrument
Cluster Section 414 - 00 .
B1318 9318 Battery Voltage
Low Instrument
Cluster Section 414 - 00 .
B1342 9342 ECU is Defective Instrument
Cluster INSTALL a new instrument
cluster; REFER to Instrument Cluster in this section. TEST the
system for normal operation. B1343 9343 Heated Backlight
Input Circuit Failure Instrument
Cluster Section 501 - 11 .
B1356 9356 Ignition Run
Circuit Open Instrument
Cluster Go To Pinpoint Test A .
B1364 9364 Ignition Start
Circuit Open Instrument
Cluster Go To Pinpoint Test A .
B2143 A143 Odometer NVM
Mmory Failure Instrument
Cluster Go To Pinpoint Test J .
C1284 5284 Oil Pressure
Switch Failure Instrument
Cluster Go To Pinpoint Test C .
P1197 1197 Mileage Switch
Circuit Failure Instrument
Cluster Go To Pinpoint Test J . Klj . 7 ba
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GEM Diagnostic Trouble Code (DTC) Index
DTC Description Source Action
B1218 Horn Relay Coil Circuit Short to
VBatt GEM REFER to
Section 501 - 14B .
B1312 Lamp Headlamp Input Circuit
Short to Battery GEM REFER to
Section 413 - 09 .
B1317 Battery Voltage High GEM REFER to
Section 414 - 00 .
B1318 Battery Voltage Low GEM REFER to
Section 414 - 00 .
B1322 Driver Door Ajar Circuit Short to
Ground GEM REFER to
Section 417 - 02 .
B1330 Passenger Door Ajar Circuit
Short to Ground GEM REFER to
Section 417 - 02 .
B1334 Decklid Ajar Rear Door Circuit
Short to Ground GEM REFER to
Section 417 - 02 .
B1339 Chime Input Request Circuit
Short to Battery GEM REFER to
Section 413 - 09 .
B1340 Chime Input Request Circuit
Short to Ground GEM REFER to
Section 413 - 09 .
B1342 ECU is Defective GEM Clear the DTCs. Retrieve the DTCs. If DTC B1342
is retrieved, INSTALL a new GEM. REFER to Section 419 - 10 .
B1353 Ignition Key-
In Circuit Open GEM REFER to
Section 413 - 09 .
B1359 Ignition Run/Acc Circuit Failure GEM REFER to
Section 211 - 05 .
B1396 Power Door Lock Circuit Short
to Battery GEM REFER to
Section 501 - 14B .
B1397 Power Door Unlock Circuit
Short to Battery GEM REFER to
Section 501 - 14B .
B1405 Driver Power Window Down
Circuit Short to Battery GEM REFER to
Section 501 - 11 .
B1408 Driver Power Window Up
Circuit Short to Battery GEM REFER to
Section 501 - 11 .
B1426 Lamp Safety Belt Circuit Short
to Battery GEM Go To Pinpoint Test K .
B1428 Lamp Safety Belt Circuit Failure GEM Go To Pinpoint Test K .
B1431 Wiper Brake/Run Relay Circuit
Failure GEM REFER to
Section 501 - 16 .
B1432 Wiper Brake/Run Relay Circuit
Short to Battery GEM REFER to
Section 501 - 16 .
B1434 Wiper Hi/Low Speed Relay Coil
Circuit Failure GEM REFER to
Section 501 - 16 .
B1436 Wiper Hi/Low Speed Relay Coil
Circuit Short to Battery GEM REFER to
Section 501 - 16 .
B1438 Wiper Mode Select Switch
Circuit Failure GEM REFER to
Section 501 - 16 .
B1441 Wiper Mode Select Switch
Circuit Short to Ground GEM REFER to
Section 501 - 16 . Klj . 8 ba
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PINPOINT TEST N: THE CHECK FUEL CAP INDICATOR IS NEVER
ON Test Step Result / Action to Take
M1 CHECK THE O/D OFF
INDICATOR OPERATION z
Key in ON position.
z Observe the O/D OFF indicator.
z Is the O/D OFF indicator
always on? Yes
GO to
M2 .
No
GO to M3 .
M2 CHECK THE INSTRUMENT
CLUSTER z
Key in OFF position.
z Disconnect: Instrument Cluster
C220a.
z Key in ON position.
z Observe the O/D OFF indicator.
z Did the indicator turn off? Yes
REFER to the Powertrain Control/Emissions Diagnosis
(PC/ED) manual.
No
GO to
M4 .
M3 CHECK THE INSTRUMENT
CLUSTER OPERATION z
Carry out the instrument cluster
self- diagnostic mode.
z Did the O/D OFF indicator
illuminate? Yes
REFER to the Powertrain Control/Emissions Diagnosis
(PC/ED) manual.
No
GO to
M4 .
M4 CHECK FOR CORRECT
INSTRUMENT CLUSTER
OPERATION z
Disconnect all instrument cluster
connectors.
z Check for:
zcorrosion
z pushed- out pins
z Connect all instrument cluster
connectors and make sure they
seat correctly.
z Operate the system and verify
the concern is still present.
z Is the concern still present? Yes
INSTALL a new instrument cluster. REFER to
Instrument Cluster
in this section. TEST the system for
normal operation.
No
The system is operating correctly at this time. Concern
may have been caused by a loose or corroded
connector. CLEAR the DTCs. REPEAT the self- test. Test Step Result / Action to Take
N1 RETREIVE AND RECORD DTCS FROM
CONTINUOUS AND ON- DEMAND SELF-TESTS—
PCM NOTE:
Once the check fuel cap indicator
does turn on, it does not turn off unless the
fuel cap has been correctly secured and the
vehicle has been driven for several minutes.
z Use recorded PCM DTCs from the
continuous and on- demand self-test.
z Are any DTCs recorded? Yes
If PCM DTC P0457, REFER to the
Powertrain Control/Emissions Diagnosis
(PC/ED) manual.
No
GO to
N2 .
N2 CARRY OUT THE INSTRUMENT CLUSTER Klj . 27 ba
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4. If the concern remains after the inspection, connect the diagnostic tool to the data link connector
(DLC) located beneath the instrument panel and select the vehicle to be tested from the
diagnostic tool menu. If the diagnostic tool does not communicate with the vehicle:
zcheck that the program card is correctly installed.
z check the connections to the vehicle.
z check the ignition switch position.
5. If the diagnostic tool still does not communicate with the vehicle, refer to the diagnostic tool manual.
6. Carry out the Data Link Diagnostic Test. If the diagnostic tool responds with: zCKT914, CKT915 or CKT70 = ALL ECUS NO RESP/NOT EQUIP, refer to Section 418 -
00 .
z NO RESP/NOT EQUIP for GEM, go to Pinpoint Test A.
z NO RESP/NOT EQUIP for RCM, refer to Section 501 - 20B .
z SYSTEM PASSED, retrieve and record the continuous diagnostic trouble codes (DTCs),
erase the continuous DTCs and carry out self- test diagnostics for the GEM.
7. If the DTCs retrieved are related to the concern, go to the GEM Diagnostic Trouble Code (DTC) Index to continue diagnostics.
8. If no DTCs related to the concern are retrieved, proceed to the Symptom Chart to continue diagnostics.
9. If the DTCs retrieved are for the RCM, refer to Section 501 - 20B .
Visual Inspection Chart Mechanical Electrical
z
Switch(es) z
Central junction box (CJB) fuses:
„28 (15A)
„ 32 (15A)
„ 39 (5A)
z Circuitry
GEM Diagnostic Trouble Code (DTC) Index DTC Description Source Action
B1340 Chime Input Request
Circuit Short to Ground GEM Go To Pinpoint Test C .
B1342 ECU Is Defective GEM CLEAR the DTCs. TEST the system for normal operation.
RETRIEVE the DTCs. If DTC B1342 is retrieved, INSTALL
a new GEM. REFER to
Section 419 - 10 .
B1353 Ignition Key-
In Circuit
Open GEM Go To Pinpoint Test B .
B1462 Safety Belt Switch
Circuit Failure GEM Go To Pinpoint Test F . Klj . 3 ba
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PINPOINT TEST B: POOR RECEPTION z
Are the resistances less than 5 ohms? system for normal
operation.
No
REPAIR the circuit
(s) in question. TEST
the system for
normal operation.
Test Step Result / Action to Take
B1 CHECK ANTENNA CABLE
CONNECTIONS z
Key in OFF position.
z Check the antenna connections
including the extension cable.
z Check to make sure the antenna is
securely mounted to the vehicle body
at ground points.
z Are the connections clean, secure,
and in metal- to-metal contact? Yes
GO to
B2 .
No
CLEAN and SECURE the antenna connections
as necessary. TEST the system for normal
operation. B2 CHECK SUPPRESSION
EQUIPMENT/MOUNTING AND
CONNECTING CIRCUITS z
Check all necessary suppression
equipment and the radio frequency
interference suppression bond. Refer
to Section 415 - 01 .
z Check the radio receiver hood bonding
strap and the body- to-chassis straps
for integrity, cleanliness, and metal- to-
metal contact.
z NOTE: The capacitor mounting points
are used to complete the electrical
circuit and must be mounted securely
to clean surfaces.
z Check the mounting and connecting
circuits of the radio ignition interference
capacitor for integrity, cleanliness, and
metal- to-metal contact.
z Are the connections clean, secure,
and in metal- to-metal contact? Yes
GO to
B3 .
No
CLEAN, SECURE, or INSTALL new suppression
equipment as necessary. TEST the system for
normal operation. B3 CHECK RADIO IGNITION
INTERFERENCE CAPACITOR z
Check the operation of the radio
ignition interference capacitor by
substituting it with a known good
component.
z Key in START position.
z Turn the audio unit on and check the
radio reception. Yes
INSTALL a new radio ignition interference
capacitor. TEST the system for normal operation.
No
GO to
B4 . Klj . 5 ba
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4. If the concern remains after the inspection, connect the scan tool to the data link connector
(DLC) located beneath the instrument panel and select the vehicle to be tested from the scan
tool menu. If the scan tool does not communicate with the vehicle:
zcheck that the program card is correctly installed.
z check the connections to the vehicle.
z check the ignition switch position.
5. If the scan tool still does not communicate with the vehicle, refer to the scan tool manual.
6. Carry out the DATA LINK DIAGNOSTIC TEST. If the scan tool responds with: zCKT914, CKT915 or CKT70 = ALL ECUS NO RESP/NOT EQUIP, refer to Section 418 -
00 .
z NO RESP/NOT EQUIP for GEM, go to Pinpoint Test A.
z SYSTEM PASSED, retrieve and record the continuous diagnostic trouble codes (DTCs),
erase the continuous DTCs and carry out self- test diagnostics for the GEM.
7. If the DTCs retrieved are related to the concern, go to GEM Diagnostic Trouble Code (DTC) Index to continue diagnostics.
8. If no DTCs related to the concern are retrieved, proceed to Symptom Chart to continue diagnostics.
GEM Diagnostic Trouble Code (DTC) Index Visual Inspection Chart Mechanical Electrical
z
Switch(es) z
CJB Fuses:
„7 (20A)
„ 32 (15A)
„ 39 (5A)
z Wiring harness
z Connections
z Lamps
z Circuitry
GEM Diagnostic Trouble Code (DTC) Index DTC Description Source Action
B1322 Driver Door Ajar Circuit
Short to Ground GEM REFER to
Section 417 - 02 .
B1330 Passenger Door Ajar Circuit
Short to Ground GEM REFER to
Section 417 - 02 .
B1334 Decklid Ajar Rear Door
Circuit Short to Ground GEM REFER to
Section 417 - 02 .
B1342 ECU Is Defective GEM CLEAR the DTC. Retrieve the DTCs. If DTC B1342 is
retrieved, INSTALL a new GEM. For additional information, REFER to Section 419 - 10 .
B1397 Power Door unlock Circuit
Short to Battery GEM REFER to
Section 501 - 14B .
B1405 Driver Power Window Down
Circuit Short to Battery GEM REFER to
Section 501 - 11 . Klj . 3 ba
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